The NIMH Collaborative HIV/STD Prevention Trial is a two-arm randomized, community-level trial being conducted in five countries--China, India, Peru, Russia, and Zimbabwe. It is the first international test of a community-level prevention program based on the theory of diffusion of innovations utilizing Community Public Opinion Leaders (C-POLs). Based on a set of ethnographic studies conducted over 18 months and a series of epidemiological studies with over 9000 participants in the five countries, an assessment and the CPOL intervention have been culturally adapted, piloted and mounted in randomly chosen venues in each country. The intervention's efficacy in reducing self-reported behavioral risk with non-spousal partners and incident sexually transmitted diseases is being assessed based on a baseline, 12- and 24- month interviews and collection of biological specimens. After conducting the 24-month assessment, the intervention will be provided in the comparison venues. This proposal requests three years of funding to complete the randomized controlled trial in each site; the extended period is requested because of the extra time required at the initiation of the study to conduct multiple epidemiological and ethnographic studies to ensure cross-site comparability and within-site validity to all assessments, intervention, and data collection and reporting processes. The results of this trial should provide the first documentation and evaluation of the portability and adaptability of interventions cross nationally and cross-culturally and is being designed and implemented to be realistic and feasible for replication and dissemination. During the past year, the baseline and intervention were implemented in one city (Lima), and the first follow-up will occur in Lima in Year 5 as well. During Year 6, we will conduct the second follow-up in Lima, and then provide the intervention in the control venues in Lima. We will also implement the baseline and intervention in Chiclayo and Trujillo. During Year 7, we will continue the intervention in Chiclayo and Trujillo, and conduct the first follow-up assessment. During Year 8, we will complete the intervention in Chiclayo and Trujillo, as well as the 24-month follow-up and the intervention in the control communities. The remaining time will be used for data analysis.